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Electrolysis of neodymium oxide. Final report for the period August 19, 1991 through February 28, 1997
The objective of this research was to develop an electrolytic process for the continuous and economic production of neodymium alloys from neodymium oxide. The electrolysis of neodymium oxide continued to show promise for implementation as a low-cost process to produce high- quality neodymium or neodymium-iron alloy
Heavier drinking American college students may self-select into study abroad programs: An examination of sex and ethnic differences within a high-risk group
As with other heavier drinking groups, heavier drinking American college students may self-select into study abroad programs with specific intentions to use alcohol in the foreign environment. This cross-sectional study used a sample of 2144 students (mean age = 20.00, SD = 1.47) to explore differences in alcohol use and related negative consequences among (1) students intending to study abroad while in college, (2) students not intending to study abroad, and (3) students reporting prior study abroad participation. Results revealed that participants with no intention to study abroad drank less and experienced fewer alcohol-related consequences than participants intending to study abroad. In addition, students reporting prior completion of study abroad programs drank more and reported more hazardous alcohol use than those not intending to study abroad. Ethnic and sex differences existed; with White students, males, and females intending to study abroad and non-White students who previously completed study abroad programs demonstrating the most risk. These findings provide empirical support that study abroad students may be a heavier drinking subgroup necessitating intervention prior to beginning programs abroad
K-U Studies of Silica-Rich Inclusions in the Shaw Chondrite
The K/U can be regarded as a "planetary constant" which is invariant during magmatic processes but which differs for cosmochemical reasons between planets. This assumption is
universal in all thermal history calculations for planets. K-SiO_2-rich inclusions are found in Shaw which many authors believe is a chondrite which has been subjected to partial melting (Taylor et al., 1979; Rambaldi and Lamimer, 1976). Although the origin of these inclusions is not well understood, it is possible that they represent the first melts or magmatic fluids produced in the formation of planets. Thus it is of interest to see if U and Th have followed K into these liquids. For the case of Shaw some evidence of K/REE fractionation already exists (Rambaldi and Lamimer, 1976). Six polished sections of Shaw with affixed mica fission track detectors were irradiated with
~ 2 x 10^(18)/cm^2 thermal neutrons. Excellent fission track images were obtained with no evidence for any significant contamination. (Random scans on our most-studied section gave 6 ppb U.) The fission track distributions show a high degree of localization. In one section, mapped in great detail, 20-30 large (> 50 micron) fission track localizations, can all be accounted for by whitlockite and chloroapatite. The whitlockite U concentrations (300-700 ppb) are variable, but typical for
chondrites. The phosphate grains serve as fiducial points, allowing accurate location of the melt inclusions on the mica track detector (maximum position error= 20 microns). In many cases no localizations of tracks are found (U contents < 10 ppb) corresponding to the K-Si-rich inclusions, but in 7/25 cases localizations are found with U concentrations up to ~ 300 ppb. The inclusions are small (usually< 20μ), and there are many other small track localizations in this size range which have no obvious sources, thus some of these 7 cases may be accidental. However, track mapping at 13 random fields of view showed only 2 localizations (track density 3-4 times surroundings) within 20 microns. The small track localizations of unknown origin can be explained by a combination of buried sources (within 10 microns of surface), local contamination (which can never be ruled out) or localization of U on grain boundaries or cleavage planes in major phases. There is no correlation of U content with inclusion chemistry (K), size, opaque mineralogy, or petrographic location. Many of the inclusions are within large (hundreds of microns) olivine grains, including some that seem U-rich. In two of these cases the track localizations stand out from an almost blank background and match the location and size of the inclusion. It seems inescapable that the tracks do
arise from the inclusions in these cases. It may be that these inclusions were a preferential site of contamination during sample preparation or by terrestrial weathering, but it is also possible that U-bearing phases only occasionally participated in the partial melting process. It may be significant that the inclusions contain no P, thus this U reservoir has not participated. Regardless, the important
result is that in most cases K was mobilized to a much higher degree than U in the Shaw partial melting event. (The inclusion KIU is at least 10x bulk chondrites.) Although the inclusions are relatively Fe-rich, the concentration of K and Si and the exclusion of U and rare-earths follows the chemical systematics of immiscible silicate melts (Watson, 1976; Ryerson and Hess, 1978). To the extent that Shaw is representative of very small degrees of partial melting in planets, K and U appear to be fractionated
An exploratory cluster randomised trial of a university halls of residence based social norms marketing campaign to reduce alcohol consumption among 1st year students
<p>Aims: This exploratory trial examines the feasibility of implementing a social norms marketing campaign to reduce student drinking in universities in Wales, and evaluating it using cluster randomised trial methodology.</p>
<p>Methods: Fifty residence halls in 4 universities in Wales were randomly assigned to intervention or control arms. Web and paper surveys were distributed to students within these halls (n = 3800), assessing exposure/contamination, recall of and evaluative responses to intervention messages, perceived drinking norms and personal drinking behaviour. Measures included the Drinking Norms Rating Form, the Daily Drinking Questionnaire and AUDIT-C.</p>
<p>Results: A response rate of 15% (n = 554) was achieved, varying substantially between sites. Intervention posters were seen by 80% and 43% of students in intervention and control halls respectively, with most remaining materials seen by a minority in both groups. Intervention messages were rated as credible and relevant by little more than half of students, though fewer felt they would influence their behaviour, with lighter drinkers more likely to perceive messages as credible. No differences in perceived norms were observed between intervention and control groups. Students reporting having seen intervention materials reported lower descriptive and injunctive norms than those who did not.</p>
<p>Conclusions: Attention is needed to enhancing exposure, credibility and perceived relevance of intervention messages, particularly among heavier drinkers, before definitive evaluation can be recommended. A definitive evaluation would need to consider how it would achieve sufficient response rates, whilst hall-level cluster randomisation appears subject to a significant degree of contamination.</p>
Group Identification as a Moderator of the Relationship Between Perceived Social Norms and Alcohol Consumption
Previous research has shown that social norms are among the strongest predictors of college student drinking. Among college students, perceiving that “others” drink heavier relative to themselves has been strongly and consistently associated with heavier drinking. Research has also shown that the more specifically “others” are defined, the stronger the association with one’s own drinking. The present research evaluated whether group identification as defined by feeling closer to specific groups moderates the associations between perceived drinking norms in the group and one’s own drinking. Participants included 3752 (61% Female) students who completed online assessments of their perceived drinking norms for four groups of students on their campus as well as identification with each group and participants’ own drinking behavior. Results indicated that greater identification with same-sex students, same-race students, and same-Greek-status students were associated with stronger relationships between perceived drinking norms in the specific groups and own drinking
Environmental shaping of codon usage and functional adaptation across microbial communities.
Microbial communities represent the largest portion of the Earth's biomass. Metagenomics projects use high-throughput sequencing to survey these communities and shed light on genetic capabilities that enable microbes to inhabit every corner of the biosphere. Metagenome studies are generally based on (i) classifying and ranking functions of identified genes; and (ii) estimating the phyletic distribution of constituent microbial species. To understand microbial communities at the systems level, it is necessary to extend these studies beyond the species' boundaries and capture higher levels of metabolic complexity. We evaluated 11 metagenome samples and demonstrated that microbes inhabiting the same ecological niche share common preferences for synonymous codons, regardless of their phylogeny. By exploring concepts of translational optimization through codon usage adaptation, we demonstrated that community-wide bias in codon usage can be used as a prediction tool for lifestyle-specific genes across the entire microbial community, effectively considering microbial communities as meta-genomes. These findings set up a 'functional metagenomics' platform for the identification of genes relevant for adaptations of entire microbial communities to environments. Our results provide valuable arguments in defining the concept of microbial species through the context of their interactions within the community
Brief motivational interventions for college student drinking may not be as powerful as we think: An individual participant-level data meta-analysis
Background For over two decades, brief motivational interventions (BMIs) have been implemented on college campuses to reduce heavy drinking and related negative consequences. Such interventions include in-person motivational interviews (MIs), often incorporating personalized feedback (PF), and stand-alone PF interventions delivered via mail, computer, or the Web. Both narrative and meta-analytic reviews using aggregate data from published studies suggest at least short-term efficacy of BMIs, although overall effect sizes have been small. Method The present study was an individual participant-level data (IPD) meta-analysis of 17 randomized clinical trials evaluating BMIs. Unlike typical meta-analysis based on summary data, IPD meta-analysis allows for an analysis that correctly accommodates the sampling, sample characteristics, and distributions of the pooled data. In particular, highly skewed distributions with many zeroes are typical for drinking outcomes, but have not been adequately accounted for in existing studies. Data are from Project INTEGRATE, one of the largest IPD meta-analysis projects to date in alcohol intervention research, representing 6,713 individuals each with two to five repeated measures up to 12 months post-baseline. Results We used Bayesian multilevel over-dispersed Poisson hurdle models to estimate intervention effects on drinks per week and peak drinking, and Gaussian models for alcohol problems. Estimates of overall intervention effects were very small and not statistically significant for any of the outcomes. We further conducted post hoc comparisons of three intervention types (Individual MI with PF, PF only, and Group MI) vs. control. There was a small, statistically significant reduction in alcohol problems among participants who received an individual MI with PF. Short-term and long-term results were similar. Conclusions The present study questions the efficacy and magnitude of effects of BMIs for college drinking prevention and intervention and suggests a need for the development of more effective intervention strategies
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